From: Steven Price <steven.price@xxxxxxx>
If SVE is enabled then 'ret' can be assigned the return value of
kvm_vcpu_enable_sve() which may be 0 causing future "goto out" sites to
erroneously return 0 on failure rather than -EINVAL as expected.
Remove the initialisation of 'ret' and make setting the return value
explicit to avoid this situation in the future.
Fixes: 9a3cdf26e336 ("KVM: arm64/sve: Allow userspace to enable SVE for vcpus")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Steven Price <steven.price@xxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200617105456.28245-1-steven.price@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/kvm/reset.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -258,7 +258,7 @@ static int kvm_vcpu_enable_ptrauth(struc
int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
{
const struct kvm_regs *cpu_reset;
- int ret = -EINVAL;
+ int ret;
bool loaded;
/* Reset PMU outside of the non-preemptible section */
@@ -281,15 +281,19 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu
if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, vcpu->arch.features) ||
test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, vcpu->arch.features)) {
- if (kvm_vcpu_enable_ptrauth(vcpu))
+ if (kvm_vcpu_enable_ptrauth(vcpu)) {
+ ret = -EINVAL;
goto out;
+ }
}
switch (vcpu->arch.target) {
default:
if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
- if (!cpu_has_32bit_el1())
+ if (!cpu_has_32bit_el1()) {
+ ret = -EINVAL;
goto out;
+ }
cpu_reset = &default_regs_reset32;
} else {
cpu_reset = &default_regs_reset;
